https:/.../media.mp4

Hello everyone.

I'm Himani Patel pursuing a bachelor's of science in biology from the University of

Nebraska Lincoln. I'm from India.

I am an aspiring biologist and bioinformatician.

Focus of my research

is climate change and

Conservation biology.

My project is funded and supported by Undergraduate Creative Activities and

Research Experience. Also known as UCARE,

I'm grateful to get this chance to, you know,

present my research through UCARE. Um,

Today, I'll be talking about how the increasing temperatures affect the metabolic

rate and physiology of the invasive, freshwater

species, Potamopyrgus antipodarum. weird name,

right? But you can call it New Zealand mud

snail. Let us first talk about invasive alien species and climate

change.

These two factors at the leading cause of species extinction and

biodiversity loss.

Invasive alien species are the organisms non-native to the

ecosystem, which negatively impacts native biodiversity.

The invasive alien species are mostly resilient and can survive a

wide range of temperatures, salinity,

altitude and other abiotic factors while the native species are not

resilient. So they are led to extinction in the long run.

So now there are

some research evidences that suggest that with climate change,

the invasion rate will increase. However,

the question remains, how do the invaders,

survive increasing temperature and what genetic

phenotypic and physiological factors help them thrive?

How does the metabolic plasticity play a role in their invasive

potential?

Answering these questions will help us figure out ways to combat

invasive alien species and save biodiversity. By saving

biodiversity; We will mitigate the risk of climate change.

And that, in turn, will decrease the rate of invasion.

To fill in this knowledge gap,

I developed the experiment where I compare the metabolic rate of these

snails at different temperatures.

But before I explain

my experiment, let me introduce my model organism, New Zealand Mud

Snail. Um, it is very tiny four to six millimeters in length.

Um, you can also see the size comparison with a dime.

These nails are impressively resilient and they spread,

or I should say they invade new ecosystem by surviving on a fishing

gear or a boat and they travel wherever we,

humans,

travel. Now, why do I use

this model to investigate the effects of climate change?

Well, this snail

can survive wide range of temperatures,

and we can see that because this snail has invaded all continents in

last 150 years.

This gives us the opportunity to investigate and compare the metabolic response

of this snail across different environmental conditions.

So, this is the best model for my research.

I used five lineages of 37A mitochondrial haplotype.

Now what does that mean?

That means that all lineages in that haplotype will have the same

mitochondrial genome, but they will have a variation in their nuclear genome.

We collected these snails from the lake in New Zealand called Mapourika.

So what is the specific research
question I'm trying to answer?

How does the metabolic rate of
New Zealand mud snail change with

elevated temperature
across different lineages?

What are the approaches I used?
first is respirometry,

I measured the whole organisms
metabolic rate at 16 degrees Celsius and

22 degrees Celsius. 2. Global
metabolic profiling,

where I performed enzyme assays,

which gave us the physiological
comparison between these lineages

3. nuclear genome analysis.

This is the extension of my research where
I'll be doing bioinformatics analysis

to see if there are any genetic
basis of the metabolic plasticity.

Now, what was the experimental
design? very straightforward.

The five different lineages
were used in this experiment.

The control group was kept at
16 degrees Celsius for two weeks.

The whole organism's
metabolic rate was measured.

The snails were sacrificed and
the whole body issue was frozen in

liquid nitrogen.

And it was stored at negative
80 degrees Celsius for further

analysis. Um,

the same process was followed for the
22 degrees Celsius experimental group.

And after designing this experiment,

we hypothesized that the metabolic
rate should increase with

increasing temperature
for all lineages, right?

It makes sense that it should increase
if we increase the temperature.

Now you might.

Wonder how do we measure the
whole organisms metabolic rate?

We use respirometer
to do that. There's a small,

small Water-filled chamber
inside of the respirometer,

and it is attached,
to an incubator, which, uh,

controls the temperature of that chamber.

So we put our snail inside that
chamber for about 45 minutes. Um,

the snail respires inside the chamber,

and there is a drop in
the oxygen concentration,

which is measured by the
electrode attached to the chamber.

As you see on the screen.

It gives you a

beautiful graph on the computer,

which tells us the change in
oxygen concentration with time.

This is the snail stock room image,
and this is me working with snails,

changing the water and feeding them

After data collection.

I performed ANOVA analysis and
built these beautiful graphs.

The P-value on the graph suggests
that there is a significant

difference between the metabolic rate
of these lineages at both temperatures,

as you can see,

MP 18-19 in Green has lower
metabolic rate at 16 degrees

Celsius than MP 18-8 in purple. Now,

if you compare the rates at
22 degrees Celcius,

it's the other way around. MP 18-19

lineage has increased the metabolic
rate with increasing temperature.

Whereas the MP 18-8

has lowered the metabolic
rate at elevated temperature.

So what can we conclude from this graph?

We can say that there is a significant
difference in metabolic rate of the

lineages. And that might
be due to the change,

the variation in the nuclear genome.

Then I performed two factors ANOVA
analysis, which gave this graph,

um, where you can see
that only one lineage,

show a significant increase in
the metabolic rate with increasing

temperature, um, MP 18-19, the green one,

the red MP-18-9 show an increase,

but it is not significant orange
and blue lineages have almost the

same metabolic rate at
both temperatures. However,

MP 18-8 in purple show a
decrease in metabolic rate with

elevated temperature.

So the initial hypothesis stated that
the metabolic rates would increase

for all of the lineages with increasing
temperature. It is only true for one of the

lineages and not the rest.

To find out the reasons.

We need to extend this research
and extend this experiment.

Um, and

that brings us to conclusions and
future directions. From the results,

We can conclude that there is a standing
genetic variation in the natural

snail population,

which is affecting their metabolic
rate at different temperatures.

And this should be due to a
variation in their nuclear genome,

as they shared the same
mitochondrial genome.

The extension of this research
would be to analyze the genome for

the single nucleotide polymorphisms sites.

It's also known as SNP sites
to get a better understanding of

how the metabolic rate is
changing with temperature.

With that, I will conclude my talk. And
if you would like to follow my work,

my research, please follow me on
Twitter on this handle, Himani_D_Patel.

And I would love to connect with
you and answer any questions you may

have. Thank you.